geenforce: fix re-publish FK crash on MySQL (stale entries in draft rebuild)

replace_scope_draft deleted old draft entries with per-object db.session.delete
but left the deleted objects in scope.entries. On a re-publish a caller
(seed_display_scope) then matched a stale deleted entry via next() and
store_inline_payload attached a payload to its dead entryid, failing the
manifestpayloads->manifestentries FK on MySQL (1452); SQLite does not enforce
it so the idempotency test passed. Clear the collection via the delete-orphan
cascade instead, and flush pending inserts before the bulk payload delete so its
autoflush cannot interleave a half-built insert. Verified publish + re-publish
x3 on MySQL 5.6.

plugins/geenforce/service.py

@@ -57,8 +57,14 @@ def replace_scope_draft(scopename, phase, manifest):
     scope.site = manifest.get('Site')
     scope.iscommon = (scopename == 'common')
 
-    for entry in list(scope.entries):
-        db.session.delete(entry)
+    # Clear existing draft entries via the delete-orphan cascade. This also
+    # EMPTIES the in-memory collection, so a later lookup on scope.entries cannot
+    # match a stale (deleted) entry. A per-object db.session.delete() leaves the
+    # deleted objects in scope.entries until expiry, which on a re-publish made a
+    # caller (seed_display_scope) pick an old deleted entry and attach a payload
+    # to its dead entryid -> MySQL FK 1452 (SQLite does not enforce it, so the
+    # idempotency test missed it).
+    scope.entries.clear()
     db.session.flush()
 
     for i, entry_dict in enumerate(manifest.get('Applications') or []):
@@ -352,7 +358,15 @@ def store_inline_payload(entry, filename, contenttype, rawbytes):
     Returns the ManifestPayload.
     """
     sha = hashlib.sha256(rawbytes).hexdigest()
-    ManifestPayload.query.filter_by(entryid=entry.entryid).delete()
+    # Flush any pending inserts (e.g. a prior entry's inline payload) BEFORE the
+    # bulk delete. Otherwise the delete's autoflush interleaves that half-built
+    # INSERT and, on MySQL, fails the manifestpayloads->manifestentries FK
+    # (SQLite does not enforce it the same way, so tests miss this). Then delete
+    # existing rows for this entry with autoflush off + no session-sync.
+    db.session.flush()
+    with db.session.no_autoflush:
+        ManifestPayload.query.filter_by(
+            entryid=entry.entryid).delete(synchronize_session=False)
     db.session.flush()
     payload = ManifestPayload(
         entryid=entry.entryid,